Abstract: An apparatus and a method for interference cancellation in a transmitting end of a multi-antenna system are provided. A precode is generated which maximizes a diversity gain of one or more receive antennas using channel information of the receive antennas to be serviced. Transmit powers of the receive antennas are updated by taking into account a power loss and a shaping loss according to a dirty paper coding. Transmit signals are precoded by updating the precode according to the updated transmit powers. The dirty paper coding is performed on the precoded transmit signals to be transmitted to the receive antennas.

Abstract: An apparatus and method for generating an effective Signal to Noise Ratio (SNR) per stream in a Multiple Input Multiple Output (MIMO) wireless communication system is disclosed. The apparatus includes a selector, a calculator, a generator, and a decider. The selector selects effective streams among whole streams. The calculator calculates a relative SNR rate between the effective streams. The generator generates an equation having as a solution an SNR of a first effective stream. The decider decides an SNR per effective stream using the solution of the equation and the relative SNR rate.

Abstract: A method and apparatus for selecting an antenna in a communication system is provided. The apparatus includes a mobile station for determining a set of transmit antennas by considering statistical channel information, for determining a subset of the transmit antennas, which can increase a diversity gain and reduce an effect of a spatial correlation, from among the determined set of the transmit antennas by considering the statistical channel information and instantaneous channel information, for generating antenna selection information by using the determined subset of the transmit antennas, and for feeding back the generated antenna selection information to a base station.

Abstract: A mobile communication system for modulating input data with a specific size into an OFDM (Orthogonal Frequency Division Multiplexing) symbol and transmitting the OFDM symbol through at least two different antennas. A replica generator generates replica data by cyclically-circulating the input data. An encoder generates a first antenna signal and a second antenna signal by encoding the input data and the replica data. A first IFFT (Inverse Fast Fourier Transform) block generates a first OFDM symbol by performing IFFT on the first antenna signal, and a second IFFT block generates a second OFDM symbol by performing IFFT on the second antenna signal. A first antenna transmits the first OFDM symbol, and a second antenna transmits the second OFDM symbol.

Abstract: A mobile communication system for modulating input data with a specific size into an OFDM (Orthogonal Frequency Division Multiplexing) symbol and transmitting the OFDM symbol through at least two different antennas. A replica generator generates replica data by cyclically-circulating the input data. An encoder generates a first antenna signal and a second antenna signal by encoding the input data and the replica data. A first IFFT (Inverse Fast Fourier Transform) block generates a first OFDM symbol by performing IFFT on the first antenna signal, and a second IFFT block generates a second OFDM symbol by performing IFFT on the second antenna signal. A first antenna transmits the first OFDM symbol, and a second antenna transmits the second OFDM symbol.

Abstract: A signal transmission method for a multiple input multiple output (MIMO) communication system. A transmitter having a plurality of transmission antennas receives antenna selection information from a receiver having at least one reception antenna. The transmitter selects at least two transmission antennas based on the antenna selection information, beamforms space-time block coding (STBC)-coded input signals with a weighting matrix, and transmits the beamformed signals via the selected transmission antennas. The antenna selection information is generated based on exact channel characteristics and statistical channel characteristics for the transmission antennas and a spatial correlation between the transmission antennas.

Abstract: A transmitter of a Diagonal Bell Laboratories Layered Space-Time (DBLAST) system includes an interleaver for performing interleaving for all sub-streams in a stream of a transmission signal, thereby generating an interleaved signal, a symbol repeater for generating a reverse-arranged signal rearranged in a reverse order to the interleaved signal, and a DBLAST transmit unit for transmitting the interleaved signal and the reverse-arranged signal through multiple transmit antennas. A receiver of a DBLAST system includes a DBLAST receive unit for receiving signals through multiple transmit antennas, a repeating symbol combiner for generating a combined signal; a deinterleaver for generating a deinterleaved signal; and a decoder for decoding the deinterleaved signal.

Abstract: A transmission method and apparatus in a mobile communication system, which modulates input data with a specific size into an OFDM symbol before transmission. In the transmission apparatus, a controller determines to transmit replica data instead of the input data, if the input data is retransmission data. A replica generator generates replica data by cyclically-circulating the input data under the control of the controller. An IFFT block generates an OFDM symbol by IFFT-transforming the replica data.

Abstract: A mobile communication system modulates input data with a specific size into an OFDM symbol and transmits the OFDM symbol through an antenna. In the mobile communication system, a replica generator generates replica data by cyclic-circulating the input data by a predetermined cyclic circulation distance d, and outputs a stream of the input data and the replica data as a data stream. An IFFT (Inverse Fast Fourier Transform) block performs IFFT on the data stream output from the replica generator, and generates a stream of OFDM symbols.

Abstract: A mobile communication system for modulating input data with a specific size into an OFDM (Orthogonal Frequency Division Multiplexing) symbol and transmitting the OFDM symbol through at least two different antennas. A replica generator generates replica data by cyclically-circulating the input data. An encoder generates a first antenna signal and a second antenna signal by encoding the input data and the replica data. A first IFFT (Inverse Fast Fourier Transform) block generates a first OFDM symbol by performing IFFT on the first antenna signal, and a second IFFT block generates a second OFDM symbol by performing IFFT on the second antenna signal. A first antenna transmits the first OFDM symbol, and a second antenna transmits the second OFDM symbol.